IGBT's are paralleled all the time in industrial applications and driven by single driver IC's as well. You do need to know the current limits of the driver IC and the combined capacitance of the IGBT gates though. From there you can calculate what Resistance to put in series with each gate and what your peak working frequency can be based on that.
Many inverter welder, plasma cutter power supplies, and VFD's will often have H-bridge switching systems that have as many as 12 IGBT's per leg being driven off of a single gate driver IC and still be running at 25 - 40 KHZ.
However now that IGBT's are being made that can carry 1000 amps 2400 volts into the 10"s of KHZ switching frequencies there is less paralleling being done but still the gate capacitance of one large IGBT can be as much or more than what several smaller IGBT's combined are.